Device for introducing a liquid into a stream of pressurised gas



Jan. 28, 1964 United States Patent DEVICE EQR INTRODUCING A LIQUID INTOA STREAM OF PRESSURISED GAS Ronald Thomas Lawrence, Chilioway, PankridgeSt,

Crondall, England Filed Jan. 22, 1962, Ser. No. 167,843

Claims priority, application Great Britain Jan. 27, 1961 Claims. (Cl.137205.5)

The invention relates to a device for introducing a Liquid into a streamof pressurised gas to provide a mixture of liquid and gas ofpredetermined proportions and is concerned with an improvement in ormodification of the invention described and claimed in US. patentapplication No. 26,873, filed May 4, 1960, now Patent No. 3,068,885issued Dec. 18, 1962.

An object of the present invention is to provide a device which is morecompact and cheaper to produce than the devices described in theaforesaid specification.

According to the present invention a device for introducing a liquidinto a stream of pressurised gas comprises a housing having an inlet andan outlet through which, in operation, a stream of pressurised gas ispassed, the hon-sing having an internal partition positioned in theflow-path between the inlet and the outlet and containing an annularvalve seat; the device also comprising a valve member, engageable withthe seat and arranged to be lifted therefrom against a bias by the howof gas through the housing, the valve member being mounted on a guidingstem having a longitudinal throughway therein, arranged to communicateat the end thereof remote from the valve member with a source of liquidat a pressure substantially equal to the pressure of the gas upstream ofthe valve seat and at the other end thereof with an orifice in the valvemember, arranged to discharge liquid into the gas stream in a region ofreduced pressure prodnced by the flow 0d gas past the seat, the biasopposing the lifting of the valve member being such as to produce apressure drop in gas flowing through the seat, which will produce 'aliquid and gas mixture of the desired proportions.

The seat is conveniently arranged substantially horizontally and thebias opposing the lifting of the valve member is effected by the totalweight of the valve member and the stem.

Preferably the liquid is contained in a reservoir, positioned below thevalve seat, and the stem extends downwardly into the reservoir, thereservoir communicating above the level of liquid therein with theupstream side of the seating.

By way of example a lub-nioator device, for introducing a meteredquantity of oil into a stream of compressed air, will now be describedwith reference to the accompanying drawing, which is an axial sectionthrough the device.

The device comprises a valve housing 1, having an internallyscrew-threaded inlet 2 and an internally screwthreaded outlet 3 to whichpipes for conveying the compressed air can be attached. The housing 1 ismounted on top oi a reservoir for oil comprising a cylindrical wall 4-of glass or other transparent material, closed at its lower end by anend-plate 5. Sealing rings 6 are located at each end of the cylindricalwall 4. The reservoir contains a concentric tube 7 of which the upperend is belled at 12 and is located by a screwed collar 8 placed aroundthe tube 7 and engaged in a hole 9 in the underneath side of thehousing 1. The lower end of the tube 7 is located in a central hole inthe end plate 5 and is engaged and held in tension by a screwed plug 10.A sealing ring :11 is located between plug and the end plate 5. The plug10 is removed when the reservoir is to be drained or filled or when thedevice is to be disice mantled for cleaning. The collar 8 and the tube 7have a row of radially-aligned holes 13 formed thereon and whichcommunicate with an inclined passage 14, communicating with the inlet 2;thus :air flowing into the inlet 2 will pass to the interior of the tube7. The tube 7 has a second row of holes 15 adjacent the top of thereservoir and a third row of holes 16 adjacent the bottom of thereservoir. Before use, the reservoir is filled with oil to any desiredlevel, indicated by reference 17, between the rows of holes 15 and 16;thus the upper part of the reservoir will communicate through holes 15with the inlet 2 and will contain [air at substantially the inletpressure and oil will flow through the holes 16 and rise until thelevels in the reservoir and the tube 7 are substantially the same. Thebelied end 12 :of the tube 7 forms an annular seat for a lift valvemember 19, which is mounted on the top of a tubular stem, locatedconcentrically within the tube 7. The diameter of the lower end of thestem 20 is slightly smaller than the internal diameter of the tube 7 andthus the lower end of the stem acts to guide the stem for verticalmovement within the tube 7, in response to the rate of how of airthrough the inlet 2. The lower end of the stem 20 also contains an inletorifice 21, which permits a metered quantity of oil to flow up thehollow stem 20, as will hereinafter be de scribed. The valve member 19is attached to the upper end or the stem 20 by a screw 23, having a fiat24, formed thereon along the whole length of the screw. The top face ofthe valve member 19 has a fine radial groove 25 formed in it and part ofthis is covered by the head 26 of the screw, thereby forming a smalldiameter outlet orifice tor the oil. The radial groove 25 is directed inthe downstream direction, with respect to the air how, and, as willhereinafter be explained, a fine jet of oil will issue from the groove25 and will mix with the airstream just downstream of the valve seat andwill thereby form a mist.

The operation of the device is as follows, when air is flowing throughthe inlet 2, the valve member 19 is lifted from its seat 12 and so airis allowed to flow between the inlet 2 and the outlet 3. The amount ofopening of the valve member 19 depends upon the rate of flow ofcompressed air. The valve member produces a pressure drop in the air,this depending upon the amount of opening of the valve member 19. Thusthe pressure in the I immediate vicinity of the groove 25- is lower thanthe pressure of air in the upper part of the reservoir and so oil isforced up the tube 20* and emerges as a jet from the groove 25'. Due tothe fineness of the jet, the oil is dispersed in the air stream as a Therate of flow of oil depends upon the pressure drop produced by theopening of the valve member 19 and hence depends on the rate of flowthrough the housing. The loading or bias acting on the valve member inopposition to the lifting force is provided by the combined weight ofthe valve member 19 and the stem 20.

The principle :of operation of the device is similar to that of thedevices described in the aforesaid specification; but the present deviceis more compact, as the valve stem 20 also constitutes the oil supplypipe and the valve member 19 contains the discharge orifice. Thereforeseparate components are not required as in the devices described in theafioresaid specification.

The tubular valve stem 20* may be made of very light material so thatthe efiective density of the tube and the oil filling the tube willapproximate to that of the Thus as the oil level in the reservoir drops,the effective weight of the tube and the oil filling it will in crease,thereby increasing the pressure drop across the valve member to enablethe oil to be forced through the greater distance to the dischargeorifice in the valve member.

What I claim as my invention and desire to secure by Letters Patent ofthe United States is:

1. A device for introducing a liquid into a stream of pressurised gascomprising a housing having an inlet and an outlet through which, inoperation, a stream of pressurised gas is passed, the housing having aninternal partition positioned in the flow-path between the inlet and theoutlet and containing an annular substantially horizontal valve seat;the device also comprising a valve member, engageable with the seat andarranged to be lifted therefrom against a bias by the flow of gasthrough the housing; a guiding stem, extending coaxially from the valvemember and having a longitudinal throughway therein, and a reservoir,positioned below the valve seat, said stem extending downwardly into thereservoir, the latter communicating at a position above the level of theliquid therein with the upstream side of the valve seat and saidthroughway communicating at the end thereof adjacent said valve memberwith an orifice in the valve member, said orifice comprising a radialgroove in the upper surface of the valve member and communicating withthe longitudinal throughway in the stem and a cover extending over saidgroove along at least part of its length, said radial groove beingpositioned to discharge liquid into the gas stream in a region ofreduced pressure produced by the flow of gas past the seat, said biasbeing effected by the total weight of the valve member and the stem andbeing such as to produce a pressure drop in gas flowing through theseat, and thereby to produce a liquid and gas mixture of the desiredproportion, said stem being made of very light material, whereby theeffective density of the stem and the liquid contained thereinapproximates to that of the liquid.

2. A device for introducing a liquid into a stream of pressurised gascomprising a housing having an inlet and an outlet through which, inoperation, a stream of pressurised gas is passed, the housing having aninternal partition positioned in the flow-path between the inlet and theoutlet and containing an annular substantially horizontal valve seat;the device also comprising a valve member, engageable with the seat andarranged to be lifted therefrom against a bias by the how of gas throughthe housing; a guiding stem, extending coaxially from the valve memberand having a longitudinal throughway therein, and a reservoir,positioned below the valve seat, said stem extending downwardly into thereservoir, the latter communicating at a position above the level of theliquid therein with the upstream side of the valve seat and saidthroughway communicating at the end thereof adjacent said valve memberwith an orifice in the valve member, said orifice being positioned todischarge liquid into the gas stream in a region of reduced pressureproduced by the flow of gas past the seat, said bias being effected bythe total weight of the valve member and the stem and being such as toproduce a pressure drop in gas flowing through the seat, and thereby toproduce a liquid and gas mixture of the desired proportion, said stembeing movable upwardly and downwardly in a fixed guiding tube extendingfrom the reservoir and having a belled upper end, constituting the valveseat.

3. A device as claimed in claim 2 in which the guiding tube also acts tohold together the housing and the reservoir.

4. A device for introducing a liquid into a stream of pressurised gascomprising a housing having an inlet and an outlet through which, inoperation, a stream of pressurised gas is passed, the housing having aninternal partition positioned in the flow-path between the inlet and theoutlet and containing an annular substantially horizontal valve seat;the device also comprising a valve member, engageable with the seat andarranged to be lifted therefrom against a bias by the flow of gasthrough the housing; a guiding stem, extending coaxially from the valvemember and having a longitudinal throughway therein, and a reservoir,positioned below the valve seat, said stem extending downwardly into thereservoir, the latter communicating at a position above the level of theliquid therein with the upstream side of the valve seat and saidthroughway communicating at the end thereof adjacent said valve memberwith an orifice in the valve member, said orifice comprising a radialgroove in the upper surface of the valve member and communicating withthe longitudinal throughway in the stem and a cover extending over saidgroove along at least part or" its length, said radial groove beingpositioned to discharge liquid into the gas stream in a region ofreduced pressure produced by the flow of gas past the seat and said biasbeing effected by the total weight of the valve member and the stem andbeing such as to produce a pressure drop in gas flowing through the seatand thereby to produce a liquid and gas mixture of the desiredproportion.

5. A device as claimed in claim 4 in which the stem is made separatelyfrom the valve member and is secured thereto by a screw of which thehead constitutes the said cover extending over said groove along atleast part of its length.

References Cited in the file of this patent UNITED STATES PATENTS532,100 Robison Jan. 8, 1895 1,231,175 Kramer June 26, 1917 2,088,082Davis July 27, 1937 2,520,692 Powell Aug. 29, 1950 2,571,476 Ofiutt Oct.16, 1951 2,737,199 Ingram May 6, 1956 2,932,317 Klosse Apr. 12, 19603,068,885 Lawrence Dec. 18, 1962 UNITED STATES PATENT OFFICE CERTIFICATEOF CORRECTION I Patent No. 3,119,404 January 28, 1964 Ronald ThomasLawrence It is hereby certified that error appears in the above numberedpatent requiring correction and that the said Letters Patent should readas 1 corrected below. I,

In the grant, lines 1 to 3, for "Ronald Thomas Lawrence,

of Crondall, England, read Ronald Thomas Lawrence, of Crondall, England,assignor to Nuquip Limited, of Parkshot, Richmond Surrey, England, line12, for "Ronald Thomas Lawrence, his heirs" read Nuquip Limited, itssuccessors in the heading to the printed specification, lines 4 and 5,for "Ronald Thomas Lawrence, Chilloway, Pankridge St, Crondall, England"read Ronald Thomas Lawrence, Crondall, England, assignor to NuguipLimited, Parkshot, Richmond, Surrey, England Signed and sealed this 16thday of June 1964,,

(SEAL) Attest:

ERNEST W, SWIDER EDWARD J BRENNER Attesting Officer Commissioner ofPatents

1. A DEVICE FOR INTRODUCING A LIQUID INTO A STREAM OF PRESSURISED GASCOMPRISING A HOUSING HAVING AN INLET AND AN OUTLET THROUGH WHICH, INOPERATION, A STREAM OF PRESSURISED GAS IS PASSED, THE HOUSING HAVING ANINTERNAL PARTITION POSITINED IN THE FLOW-PATH BETWEEN THE INLET AND THEOUTLET AND CONTAINING AN ANNULAR SUBSTANTIALLY HORIZONTAL VALVE SEAT;THE DEVICE ALSO COMPRISING A VALVE MEMBER, ENGAGEABLE WITH THE SEAT ANDARRANGED TO BE LIFTED THEREFROM AGAINST A BIAS BY THE FLOW OF GASTHROUGH THE HOUSING; A GUIDING STEM, EXTENDING COAXIALLY FROM THE VALVEMEMBER AND HAVING A LONGITUDINAL THROUGHWAY THEREIN, AND A RESERVOIR,POSITIONED BELOW THE VALVE SEAT, SAID STEM EXTENDING DOWNWARDLY INTO THERESERVOIR, THE LATTER COMMUNICATING AT A POSTION ABOVE THE LEVEL OF THELIQUID THEREIN WITH THE UPSTREAM SIDE OF THE VALVE SEAT AND SAIDTHROUGHWAY COMMUNICATING AT THE END THEREOF ADJACENT SAID VALVE MEMBERWITH AN ORIFICE IN THE VALVE MEMBER, SAID ORIFICE COMPRISING A RADIALGROOVE IN THE UPPER SURFACE OF THE VALVE MEMBER AND COMMUNICATING WITHTHE LONGITUDINAL THROUGHWAY IN THE STEM AND A COVER EXTENDING OVER SAIDGOOVE ALONG AT LEAST PART OF ITS LENGTH, SAID RADIAL GROOVE BEINGPOSITIONED TO DISHCARGE LIQUID INTO THE GAS STREAM IN A REGION OFREDUCED PRESSURE PRODUCED BY THE FLOW OF GAS PAST THE SEAT, SAID BIASBEING EFFECTED BY THE TOTAL WEIGHT OF THE VALVE MEMBER AND THE STEM ANDBEING SUCH AS TO PRODUCE A PRESSURE DROP IN GAS FLOWING THROUGH THESEAT, AND THEREBY TO PRODUCE A LIQUID AND GAS MIXTURE OF THE DESIREDPROPORTION, SAID STEM BEING MADE OF VERY LIGHT MATERIAL, WHEREBY THEEFFECTIVE DENSITY OF THE STEM AND THE LIQUID CONTAINED THEREINAPPROXIMATES TO THAT OF THE LIQUID.